How dam removal can help rivers
From the Mesopotamian era to the modern age, dams have enabled enormous progress. They’ve helped us generate power, store water for drinking and agriculture, and manage the risk of floods. But choking up the world’s rivers and streams has had major consequences for biodiversity and people. Now many experts agree: Some dams have run their course.
BLOCKED UP
Rivers around the world have been fragmented by dams, weirs, and other barriers. These obstacles can alter water quality, threaten habitats, and disrupt the flow of nutrients, sediments, and species, impacting freshwater ecosystems and important fisheries.
Many dams constructed during the 20th century are unused, no longer economically viable, or have outlived their lifespan, degrading river health as they age.
Dams and other infrastructure are one of the main reasons freshwater species have declined faster than those in other habitats: 83% since 1970.
OUT, DAM!
Dam removals are an effective tool for bringing obstructed rivers back to life. By restoring a river’s flow, removing dams can encourage the recovery of freshwater species and habitats, providing lasting benefits for nature and communities.
After dam removal, rivers can return to close to their natural state within weeks or months and often thrive afterward.
Free-flowing rivers also provide economic benefits, cultural value, and recreational opportunities.

© WWF-US/CERYN BRAZIER
© MIKE SPRENG
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